Very hit or miss - a lot of people on IG and UT report buying trial size and it works for big MM. I know I had done this numerous times on the Nut Butter with no problem (but not recently). Some purchases go through within an hour or two, others take a week or two. Sorry -not much of an answer, just my experience.
For converting kicks the easiest way for me is to divide by 250. I have seen some people multiple by .004.
if you have time when in store, scoop up the scan kicks. First time I did it it was a real chore. You will find though that it is the same items for a while and you can develop a system of moving through the store and scanning. I usually do an extra $20+ a month just scanning. My highest has been $38. FREE MONEY!! You’ll get a monthly breakdown of how many kicks you earn from each way ie walkins, scans, receipts.
Unless it specifies then no. You can often buy trial size items.