"Frigidaire" was,some years ago, almost generic for "refrigerator" as was "Post Toasties" for dry breakfast cereal. Both have now faded into relative obscurity. Generally, of course, manufacturers/producers are pleased when their products are so widely known, but when the trademark, e.g. "Kleenex", appears, in common public use, to be substituted for the type of product it identifies "tissue", it may threaten the trademark and may cause problems for the IP lawyers of the trademark holder. However, one never hears of any such complaints from the the Sales/ Marketing Departments of those companies.