yes, definately yes. mum had a cat that couldnt quite manage his own, reminiscent of a toddler, needed a tissue and we always asked him to blow but he never did. :-D
the worst thing is not cat snot but cat phlem our cat has a cough and a cold at the mo and coughed over my jumper hopped off tail in the air and then sneezed pebble dashing the the lino lovely!
Yuck!
They do seen to get their own version of bogeys...it usually seems to dry quite a dark colour...Mmmm lovely.
It should never be yellow or green, or be copious enough to inhibit their breathing tho...that would indicate an infection.