Maybe just to play with their friends and family, to collect themselves, or to resell on the second-hand market, fans are just going crazy for the resurgence of Pokmon TCG
On the other hand, don't forget to check the actual format of the tournament, all premier events nowadays use either Standard format (cards released in last ~24-36 months) or Expanded (Black & White and newer) [2] and your M Lucario- EX is legal only in the latter one
Red has plenty of good interaction, like Chaos Warp, Tibalts Trickery, and Wild Magic Surge, so its just a case of choosing favorites
And even if you didn't, you could still play Historic that allows you to use cards now not Standard-legal you wouldn't need to stress about your deck being rotated out of use
Additionally, higher HP ultimately means more damage counters on the table, which makes for a messier gameplay experience
Down to $100 in resale value, easy