Can't Say "No"?

I frequently read, what Dan Ariely publishes and posts on behavioral economics. Today: my problem with "Just say No".

I could not agree more - we are caught in the inability to say "no".
And also the 3 reasons seem to be the same as pointed by Dan Ariely: avoidance of regret - the curse of familiarity - the future is always greener.
But what to do, in our case it is not so much about buying, but serving; it is part of our closing-the-feed-back-loop-with-our-users strategy?

Post-sales activities exceeding service contracts: double-check instrument prices and risk factors? Review instrument structures? Make a new deal type instance and deliver immediately? Conduct on site workshops on various topics? Discuss our development pipeline? Give a talk? Review a user's program? Provide featured trial periods? Discuss platform details? ......

And I think, the probability to say no goes to zero, when
  • we are invited into stimulating centers of practice, in amazing places, meeting with interesting people 
  • receiving requests from people, we know for years
  • feeling that we have lots of extra time in the (distant) future
 Although we have an important  release soon, Andreas and myself are traveling ;)