Some classes actually benifit from the Season gear over PVE Tier gear. Like the paladin retri armor, the Season gear outstood on the T4 gear.
Making that player if he wanted to stand up greatly with T4 (raid experience) to have to double the work just to make sure he does well in a raiding instance.
The change from PVE tokens to gain pvp armor isn't down to people can walk away with good pvp armor, it's to walk away with good armor in general. Some of that armor can buff their class in one way other another. Paladin retri S3 gloves (+5% dmg from Crusader Strike) is a great equip bonus for a PVE aswell a PVP'er.
PVP'ers will always be standing at a higher level of a PVE player in PVP gear. If they gain their grear via tokens, the PVP player will always have that chance to work for the next Season gear and prove they are better with thier better armor.
Guilds who sell items from PVE to any player, well it can be simple to gain the armor from buying it, but you have to work out. That the guild who is selling the items, have completed the instance, therefor put their work into wiping, clearing, working out boss encounters and to make sure they have it down 100% to sell items to un-skilled players who have alot of gold.
You wouldn't see a guild walk into BT, and within the first week take someone who is under geared, under skilled on raiding experience with them to learn new boss wipes for them to buy their gear. They do it when the instance is known to the core.