Vinyl LP's used to come with posters and all kinds of cool inserts. If you can locate most heavy metal from the 1970's through the late 1980's, if it's been taken care of, thejn it probably still has all the extra stuff. Most of the re-sissued vinyl has better audio quality than the originals, but the cover art is often not as well reproduced, and the posters or other inserts are almost never included.
The LP cover art gave some vinyl a degree of coolness that cassettes and CD's never had. In fact, the low cost of CD production (and the even lower cost of CD-R reproduction) has made CD's almost disposable -- the "8-tracks" of the early 21st century. Recording companies are phasing them out in favor of truly disposable MP-3 and other bitstreamed media to stop the copying, but without the packaging and other media to add consumer value to the music product, the only stuff that SELLS are a few really big hit songs. Most MP-3's and other bitstreamed music files have to be given away as part of a promotion for some other product; " Buy a [some product] and get free music downloads..."
Things seem to be coming "full circle". Today, bands that want to legitimize themselves nd rise above the garage-band (or garbage-band) rabble, need to have a vinyl version of their albums, or else they are just seen as another home recording act - not taken too seriously by anyone in the music business. The reason is that everyone knows a CD costs only about US$0.30 or so to produce, but an LP might run about US$1.50/unit or more. A band or artist who can move the more expensive LP product, is a band that fans think is cool enough to spend money on...so record companies respond by sinking more money into promotion, tour support, recording re-imbursements, etc.
BTW: Nice to see that metal fans aren't a bunch of queer-kissing, anti-Constitutional (2nd amendment), commmunist punks.