PayPal and Square both have a strong B2C presence. PayPal has B2C offerings focused around sending/receiving money. Square, while they don't have a strong B2C product, does spend a lot of time sticking their logo in your face every time you go to a merchant that uses Square.
By contrast, Stripe is an infrastructure company. The best parallel I can think of might be a company like Maersk (one of the world's largest container-shipping companies). Sure, you may not recognize the name if you're not in the space, but odds are that they do affect your day-to-day life as a consumer.