I agree its generous
IMC, no show means no Xp - isnt fair to the other players (who also have lives) otherwise. Normally the PC hangs at the back and only gets involved in an emergency that might effect the other players - so normally NPC'd, but occasionally run by another player if i'm feeling under pressure or it was an awkward time like a cliff hanger ending - its very rare that i'll let magic items be used or the PC be endangered unless it was getting towards a TPK without their input (if more than one no show then we play "munchkin rules" - ie we play munchkin instead)
to try and be fair to those who have genuine excuses, i'll run occasional one off solo or small group adventures for those who have dropped off the pace (eg a player who is on call at work RP's a 'trial' to go up each wizard level that earns a bit of XP to keep him up to speed, a player who had family commitments and knew he'd miss a month played a one off adventure an evening - which also covered what he'd been doing while the rest of the party were away)
At the moment i only have one character who's a level lower than the rest of the party, mainly due to no-shows. If you give more XP to characters of lower level then it stops gaps getting too great, without making the regulars feel undervalued
Just thinking about this, i remember only one complaint from a player going back a few years who missed the final encounter, and thus got a smaller share of the XP. the other players didnt have a lot of sympathy as everyone knew in advance it was the big fight.