Well, obviously, I didn't assume that myself.
Your username is I think a good one: Writers Beware. Caveat emptor, as usual, in other words.
Being in business since 1998, even if they used to do something completely different, says a small amount about the company--that the owners haven't flaked out and run off to Belize yet and have some experience in management, etc. So, it's something. No, it's not as much as people might want. But, seriously, if you're going to write papers for a living it would seem like a really good idea to learn how to read critically.
I suppose there's a possibility that they did this maliciously, but in that case, why not just lie, or at least be a lot more cunning about the half-truth? Otherwise, maybe they have a reasonable assumption that to the reader, the difference between a company that started in 1998 doing college funding help and branched out to essays in 2000 and a company doing essays since 2000 is not significant.
They could definitely be cheats and thieves in a million other ways, but this is pretty standard marketing. Just off the top of my head, the Heinz ketchup bottle says it was established in 1869, but it definitely wasn't made with high fructose corn syrup originally... and it wasn't even part of the Heinz line until the 1870s sometime, as I recall. He started out making horseradish. But, really, that's not material to the ketchup consumer.