There are many reasons people have public wishlists and hoping a random stranger will buy them a gift might be one of those reasons, but considering this happening is extremel rare, I think it might be in the minority to these other reasons:
1) One person might make a wishlist public so their own partner(s) can go look, get ideas and treat them to a new toy.
2) Simply as a list of things that person likes the look of and wants to keep them all in one place for when they have a bit of cash to treat themselves. They just left it public because they might not expect others will go looking, or might not care if they do.
3) Camgirls, pro-dommes and other similar trades have a public wishlist so their fans/subs/friends can treat them to a gift.
4) Sex toy testers (like myself) have a list of toys they want to review, so when a company gets in touch or wonders what kind of products interest you, you can send them a link, rather than try to remember all the items off the top of your head.
I'm sure there are more reasons too.
Of course, some wishlists (usually titled something like "please buy this student a gift" or similar) are obviously wishlists aimed at getting gifts. However, I don't cringe at this. I used to, but then I questioned why I felt uncomfortable about it really. Logically, if one person has the cahones to ask strangers for gifts and another stranger feels compelled to indulge that person, then nobody loses. The wishlist owner is thrilled, the sender is thrilled (usually they enjoy making someone happy. There could be more to it than selfless sending, such as hoping to strike up a naughty connection, but considering you are not allowed to post info here such as emails and there is no chat, I guess it really has to be selfless) and Lovehoney are happy, because, sales. :D
So, nobody actually loses. Everyone involved in that dynamic walks away happy with their decision. (all parties consented) Maybe we feel uncomfortable with it because most of us work hard for our treats and see it as people taking advantage and getting hand outs for free, when we personally had to spend hard earned cash. Maybe that's what makes people uncomfortable with it. Or maybe we were raised not to beg, or that begging is lowering yourself. I dunno. Point is though, it might be seen as negative (degrading, selling yourself etc) but it is that persons right to make those choices and if they feel happy with it and no one is getting hurt, then who cares really?
I obviously don't know for sure, but I suspect random wishlist treating is rare among complete strangers. Most gifting happens between people who feel they have a connection, no matter how tenious. Cam girls have fans who love to treat the women who makes their day, friends on here want to cheer up other forum members ...more often than not, there is some prior connection/friendship/relationship. Many of us humans are generous creatures, but usually to people where we get to see the outcome of our good deed lol. It makes us happy to see someone we connected with, happy.
I have a public wishlist, but I personally don't like being sent gifts. The idea behind it is lovely, but the truth is I then feel obligated to return the kindness (even IF the gifter says not to). That is my nature. I stuggle to take something without giving something back. If I am having a lean month, or had not budgeted for treats, then it becomes stressful! lol I would much rather nobody sent me gifts and I purchased my own perfect product with the money I would have used to re-gift someone. If anyone wants to cheer me up, I much prefer a chat, or a "Hey, thinking of you" or "You really helped me" comments. That makes my day.
The last few gifts I sent to others, I tried to remain anon, to avoid them feeling that same pressure (because if you don't know who did it, you can hardly return the favour) However, most of them figured it out and some sent me gifts back and then I felt awful that I had obligated them. I rarely gift these days....I can't handle the pressure of it all! lol
That's my opinion anyway.