The knowledge that large numbers of counterfeits are circulating frightens away potential collectors. The result is a drop in price for items. That effect has been seen in cast iron toys, in pattern and depression glass, in quilts, and in many other areas of collecting. The result is fewer potential buyers for a much greater pool of goods. Inevitably, prices fall.
Antiques are time travelers - ambassadors from the past.
The introduction of huge numbers of fakes into our society is diluting, distorting, demeaning, and degrading our heritage. In twenty or fifty years, they will have aged to the point where it will be much harder to tell the fake from the authentic. We will then have a situation where the poor quality of the contemporary counterfeiters is attributed to the original manufacturers of an earlier era. The love for our heritage is based substantially on our respect for the quality and care that our forbearers used in producing their material goods. So don't just wink at the repro pushers and turn away.