It depends what site you give me to find a potential partner. If you give me a site like Tinder, I believe I would find more casual dates then a long term relationship on there. If you sent me to a dating site that requires payment (in terms of being more serious) I may find a potential long term partner there. Even a successful dating website with high results of couples being together long term will do me fine.
Yeah, why not. For me it's about what I want in the moment, so it really makes no difference if I met a guy at the bar or on a dating site. The most important thing is that we both want the same thing.
I like Tinder. It's the only dating app I use and I met some really cool people there.