Greek art certainly had a powerful influence on Roman practice; the Roman poet Horace famously said that “Greece, the captive, took her savage victor captive,” meaning that Rome (though it conquered Greece) adapted much of Greece’s art (as well as importing many of its most famous works).  It is also true that many Romans copied versions of famous Greek works from earlier centuries; this is why we often have marble versions of lost Greek bronzes such as the Doryphoros by Polykleitos, which you can see below.

The Romans did not believe, as we do today, that to have a copy of an artwork was of any less value that to have the original. The copies, however, were more often variations rather than direct copies, and they had small changes made to them. The variations could be made with humor, taking the serious element of Greek art and turning it on its head.