In the early days of my flying career (long time ago, started with a few years of GA before joining the heavy stuff) we'd use to "dispense" our drained fuel by throwing it away in an arc so that most of the fuel evaporated before reaching the ground. At least we hoped so. Now in modern times (picked up intensive GA flying again) You don't make friends with witnessing people who care for the environment and airport managers, especially with "green" fields.
How do You dispense the drained fuel? Are there any provisions for that provided by the field or club? Like buckets or so?
Like in a club or rental environment with multiple flights a day, You drain every flight, or only the first flight of the day? Following the checklist does not provide for this.
Draining the wing tanks directly after refueling, I think it is unlikely You will find anything because it is still mixed, same as above, no remark about this in manuals.
Draining the engine fuel filter from a C172 requires two persons, one who has to crawl under the fuse....
I once flew a "modern" C172 in the States that had something like 11 or 13 points to check..... We still have those old buggers with only two points plus the engine...
Let's hear some opinions who does what. Please no "drain war"...yet
Richard