I use a drip pan, or more often just a piece of aluminum foil on the charcoal grate under the meat any time I'm cooking indirect. Especially when cooking chicken. I don't want all that grease dripping down into the bowl and going into the ash bucket or ash pan.
When cooking direct like steaks, hamburgers, the grease drips on the coals and burns up.
As far as cleaning, I have a 4" paint brush I use to sweep the charcoal ash off the sides of bowl and bottom that the ash sweeper don't get, but I only do that occasionally. I have a plastic putty knife I use to scrape drippings like cheese from burgers that may drip on the bowl. The aluminum foil with the grease from the last cook gets the ash bucket emptied on to it, or shake off the charcoal baskets into it, roll it up and into the trash can. My bowl has a little build up on it but I'm not scraping it down completely, just the loose pieces that tend to flake off, same as the lid.
The outside of lid and bowl gets cleaned with Windex and paper towels maybe once a month if that or if company is coming over.