Venmo is free and I use it for people I don't know well bc everyone has it. I use PayPal all the time for vendors and friends. I haven't had many people ask me to use cashapp but I like the other two fine
And my honest opinion is I love all three. I use Venmo and cash app all the time to collect money from coworkers when we order lunch and for a bunch of other things. PayPal I’ve used to online shops/vendors and I love it too