Silver bootlegs are a collector item, flac or mp3 downloads are... Just downloads
What I dont like, and I hate, are people doing crappy cdr bootlegs and selling them. I know that there are bootleggers relaseing cd-r pro, in other words, bootlegs with lightscribbed cdr instead of silver ones, with a quality printed cover and back, and sometimes a booklet. But there are people selling bad printed copies of them... That people sucks as that items doesnt have any value as collector items.
Silver pressed bootlegs are collector items that in the 90's were very easy to find and the value was in the covers, backs, and booklets. Now they are more rare but some bootlegers still release them and they worth the money, specially the ones by Crystal Cat or the Godfather. Very good packages, nice covers with great pictures. Collector items. You pay for what you get, the package.