There is a difference in materials and workmanship, no denying that. But is that difference worth an additional $2,000 or $3,000 to you? That's why Epiphone exists, and why Epiphone sells far more guitars than Gibson every year. Gibson isn't targeting their guitars for the average player, Epi is. For what Epi's cost, you're getting a very good instrument. If you want a great instrument and have the disposable income, get a Gibson. It's just that simple. Everyone's got to balance the priorities in their life: rent, car payment, wife and kids, medical bills, taxes, insurance, etc. Most people can't justify a high-end guitar, or two, or three.
There's a number of national/international touring blues bands that use Korean/Chinese import guitars, especially Epiphones. It's nothing to apologize for. I always take my Epi's to gigs and jams, (after upgrading the PU's), and invaribly get complimenmts on my tones, from the audience and musicians. A few are perplexed, as they don't think Epi's should sound that good, but that's an old prejudice. For a $100/man gig at a local bar, I wouldn't even think of taking a guitar and amp worth $4,000 or $5,000. The acoustics are bad in those places to begin with, and a smoke-filled room with lots of alcohol isn't where I take expensive possessions. Everybody's got to decide for themselves what price range guitars work for their situation.