Depending on time of day be prepared for long lines - as you mention airport possibility after - just allocate adequate time.

FYI - From the cake place to EWR airport it can be done via NJ Transit as the Hoboken station is probably the same location you would pick up a cab. NJ Transit has at minimum 1/2 hr service to Sec. Junction and train from there to EWR airport. Mostly handicap accessible assuming not too much luggage at maybe $15 p/passenger.