Dont despair!

How do you talk to guildies about raiding when PuGs do as well or better than guild runs?
What is the incentive for folks to raid with the guild? 

Typically, I talk about having fun in raids.  It is fun to kill stuff, but having fun with guildies is that and more.  When you know people in a raid, their success means a lot.  When it's just you, only YOUR success matters.  The more experienced raiders can make a difference in a raid with guildies who are less experienced.  This is how teamwork develops.  Also, for the folks who raid with the guild, they have the more tangible benefit of keeping whatever loot drops in the guild. 

When talking to these potential raiders - who are in the middle of the pack in many good PuGs, but are at the top of the list for us - I want to avoid talking about sacrifice or responsibility to the guild.  I don't want people to feel negatively about raiding with the guild.  Down that road people get burned out, and feel like to be successful they need to leave.

Ultimately, people will want to do more and they will leave.  Those who stay will be the folks who are ok with slower progression, dont mind pugging once in a while, and who really want to help out their friends once in a while.  Also, many of our guildies have been down the 'hardcore' road before.  They get stuck because of real life obligations and then realize they have to quit WoW.  Or they learn that a hobby is something to do in your spare time and moderate their WoW playing.  These folks dont need convincing that 6 hours raiding a week is plenty.  That having fun, being casual is ok . . . as long as progression happens too!