I just got off the phone with a UA FA I have known for 20+ years and she said - NO WAY!
If the plane was still on the ground they should have called back the cabin service crew and the area cleaned correctly. She also stated that they are trained on how to handle PUKE, and this was not right. She also said that this is covered in their training manuals. Vomit, blood, fecal matter, etc. Again, this is a BIO HAZARD matter, not a customer service mistake.

UA = FAIL on this one. Also, did the FA's advise the ground crew of the vomit upon landing, so the blankets could be thrown out and the area cleaned properly. If this was the last flt of the night - I would guess NOT as the planes are cleaned overnight!