[teh64]

For the first two, there are definitely people how live like that, because of surprise tech companies like Uber making it possible.

Also literally everyone and every company relies on someone else to provide some services or hardware to enable people to do their job and live. Even this conversation could not even happen without other people making sure internet connections are kept stable. This whole "one person is an island" ideology is not something a lot of people subscribe to.

Some companies don't want to spend time doing software things that are not core to their business, so they pay other companies which sometimes do it better. Most definitely not always, but for some companies it would still be better than some in-house hodgepodge.