I've run into a lot of flaky people on sites including sniffies who say they will show up then don't. I've even had some where they gave me the address and then when I got there they wouldn't give me the appt number, they just disappeared and/or blocked me. I think some of these people find it funny to string people along and then leave them hanging.
On the other hand, I've also run into the hyper impatient that are mad when I can't immediately drop everything and show up right away. I sometimes will contact people for possible hookups later, not necessarily just because I'm looking right at this moment. For one thing, people don't always respond right away anyway. It's even more annoying when people contact me and then are mad that I can't get away right now. I mean I can understand a little disappointment, sure, that's natural, but to be so mad you yell at someone and/or block them, that's a little extreme.
There are a lot of things that are annoying about those sites and apps. All the condom nazis, "sides", oral only, tops that only want to bottom, people who are super judgemental about whatever... But it mostly is what it is. I try not to take it all too seriously. When things work out, great, if not, that's life. Just keep trying.
I always try to respond to people, even if it is only to say "no thanks" or "not now" and I always try to treat people decently. I wish that everyone showed the kind of courtesy that used to be common but apparently now isn't so much.
And all the people who think that intentionally leading people on and then ghosting them is funny, well, they can go F themselves. Probably what they're doing. Jerking over how they wasted someone else's time.