"essentially all penny stocks I've seen have been
Post# of 9122
Over the last five years the fidelity OTC market index has produced an 18.8% annual return. Market data reveals the exact opposite of what you've witnessed. Maybe only the stocks you follow have fallen.
As to your question concerning listing (aka quotation) fees:
Companies do not pay fees to be quoted on OTC Link® ATS, but may elect to upgrade to the OTCQX or OTCQB marketplaces, where there are applicable fees:
Source: http://www.otcmarkets.com/learn/otc-trading
Companies must find a broker-dealer willing to quite the company. When a broker-dealer agrees, they file a form 211. A broker-dealer makes their money on the spread so it's in their best interest to offer as many stocks as they can. The more stocks they offer, the more money they earn off the spread. Currently, 130 broker-dealers are allowed to offer quotations on the electronic market.