Crazy for grass clumps - are we alone on this??

Ugh, lawn mowing day again; more grass clumps for Carly and Bo to seek out!  Not just freshly cut grass, although that will do - they search primarily for the clumps that the mower spits out periodically, mmmmmmmm, tasty!  My husband tries so hard to mow, re-mow, and re-mow a patch of lawn where I can walk them "clump-free", but they know that just beyond their reach is what they want.  They even know when they hear him mowing - and start asking to go out!  The last straw is when the mower comes in the garage to be put away - I have to barricade with "stuff" or, (and I have caught them at this) they will lick the mower for this tender treat!  Sometimes I just give up as it does not seem to affect their digestive systems one little bit.  Am I the only one with this craziness going on?  I am going to add a pic of Carly, my "old" girl, she is 13 and the worst offender - maybe it has added to her longevity?!?!  :)