I personally know of a few people with no PC or Mac along with their Amiga. Most of the rest of us can buy a cheap PC for running Windows or Linux on to do the things an Amiga can't. And I mean cheap - anyone who spends more than £300 on a PC has conned themselves out of money.
As for abandoning the Amiga - never. Not while mine is stable. If it breaks, I fully intend getting a new PPC Amiga. If there are no good choices, I won't get another computer. I certainly won't ever become a regular PC user - IMHO they aren't worth the hours of my life I'd have to spend on them.
I do feel trapped, yes, but only because the affordable computers out there are crap IBM-clones and the only two feasible OS's are horrendous. Until that changes, I'll always feel trapped.