When do you abandon a project?

I'm working on a large garter-stitch shawl in Claudia Hand Painted Yarns large loop boucle in Chocolate and Cherry. It's absolutely nothing special, altho the color is fun. The idea was to make a shawl to wear in the office when it's cold.

I'm running into 2 problems. 1) it's boring. 2) large loop boucle sheds. A lot. It's almost definitely not suitable for a "keep it at work" shawl, because the shedded bits will go all over my clothes every time I wear it.

I have knit one skein, and have 2 left in tact. I could exchange the yarn at the shop for something more suitable, and keep the one that I've knit up as a sort of anti-maccassar/cat toy.

That's the sensible thing to do - why do I feel guilty?