Why are people looking for friends on apps if they already have a big friend circle? Genuinely want to know.

So I just met this girl off a friendship app. She had this sob story about not having friends that’s there for her, and how happy she is to meet me because I don’t judge her, and I’m just happy for us to go out and have fun. No pressure or expectations just two girls going out and doing things together. Except the last two times we hung out, she keeps FaceTiming this girl who she talked to me about. She is one of the friends she claims is not there for her, and made her do a lot of stuff, also she said some lowkey racist stuff about not liking yt women but the girl she FaceTime is a yt woman. So I’m sitting there third wheeling to a FaceTime convo. Then she put me on the camera and I don’t want to be on the camera she introduced me and the girl says something slick, like I sound like Siri. I’m thinking you yt and sound like Queen Latifa but you mad I sound like Siri just because I talk proper. Also the girl I met is another proper sounding blk girl so I don’t get why my voice is such a big deal to her, That’s another story it pisses me off when people expect me to sound like ghetto hood ray just because I’m a blk girl. So I get up and tell everyone I gotta go and thanks for the invite. When I got home I was tempted to block her cause she seem lowkey fake af, and why is she friends with people she claim not there for her and that’s her sob story. Also another thing, I realise I’m paying for everything, which originally I thought okay if I pay for out tickets this one time she will pay for her food or our food next, or if I get this thing for her she will get me next. It would be like we’re at the drive through and the cashier is looking at me I’m looking at her she looking at me😂 So I’m like I’m hungry I’ll pay. This is why I like just being to myself having girlfriends is exspensive because alot of these girls are not in good financial situations, they just want live off the next friend. I was actually really looking for friends because I’m new here, and don’t know anyone here at all.