Of course your cat finds all these changes to be stressful and one of the ways for a cat to exhibit stress is by hiding (or not) and grooming for long periods. This will increase the ingestion of large quantities of fur which can accumulate in the stomach and cause gastritis and vomiting. We do see the occasional cat that has ingested something causing a blockage (ribbon is the most common), but mostly we see cats with fur ball issues causing poor appetite and/or vomiting.
A great idea for a stocking stuffer for your cat is a tube of fur ball remedy (I call it fur ball goo)! These are petroleum based laxatives that lubricate the fur in the stomach to help it pass out of the stomach and down through the GI tract and not build up into an irritating/ obstructing fur ball. There are many brands and flavors on the market such as Laxatone or Laxaire. Use the one your cat will consume! I usually suggest a tsp to tbsp of fur ball goo, given 1-2 times per week on an empty stomach.
Cats are furry and they are fastidious creatures, so anytime there is stress or changes in their environment they will groom excessively. Cats shed almost year round so giving fur ball remedy weekly all year is also a good idea. So this holiday season, get your cat a tube of fur ball remedy!