Free samples has several meanings and offering stuff for free can often result in different outcomes.
You can get a free sample at the deli counter before you buy. Usually you're there to buy so it makes sense to offer free samples. Sure someone might take advantage but typically the ratio of buying vs taking is low.
Free on the other hand, as in download this stuff free, take this free pen at the trade show, come to this free event or take an hour of my time for free has less attraction to real Buyers and usually appeals to Takers.
Takers go for anything free or close to free and place little value on what they're receiving. It's appropriate to lower your expectations and anticipate a lesser quality of response.