Since many, many design houses have versions of "inspired" bags, I am not having as many issues with this anymore. The Hermes Birkin seems to take a hint from the LV Steamer, the LV Alma is a smaller version of the Hermes Bolide, Hermes has edited at least one Gucci style, and now Ralph Lauren and LV have bags reminiscent of the Birkin. Of course the Chloe lock may have been inspired by Hermes, and one of the new Prada leather bags when carried looks a bit like a Balenciaga. Chloe's new "Big Edith" looks like the YSL Muse,which looks like a larger modification of the Bolide. Need I go on? So with everyone copying everyone (or no one having a REALLY original idea), why not have inspired bags? I don't think they cheapen the originals. You pay for a NAME, and usually the quality that goes with that name (although I know of some recent quality control issues with $1K+ designer bags), so don't expect your $49 inspired bag to last more than a season.
I have a friend who refuses to buy a nice, quality bag. Last year she fell in love with shearling trimmed bags and ended up with one for around $49--the most she had ever paid for a bag. Several months later, the handle had ripped and there was cording coming out, and the bag itself was seriously falling apart. Of course by then the whole shearling look was out, and she ended up getting a refund on the bag. But you get what you pay for...usually...and if you want a quality bag that will last, you go for the real deal. If you want a bag that will never go out of style and never have to be replaced, you go with a classic like Hermes. But if you just want to have the "IT" bag for a season, or a similar style, you can get it inexpensively. Just don't expect to have it for long!