My wife recently went web-surfing for some new earplugs; there are so many options/variables it's overwhelming. She finally called one supplier and asked for a couple (she narrowed it down to 2-3 types) samples to try. They called back and asked if they could send her a sampler. A few days later she received a really nice compartmented sampler box with an assortment of 12 pr.
(similar, but not exact) that she's now trying out for noise reduction, comfort, etc.
This is good business. Once she settles on the type(s) she likes, she'll likely be a "customer for life".