morpheus,
Who do you think should be ultimately responsible for the number of USBC members? Should it be USBC going door-to-door trying to drum up new members? Or should it be the proprietors going lane-to-lane during open play trying to get new members?
The problem is the proprietors might be making more money per lane per during open play then they are during league. Many believe bowling as entertainment is part of the reason for the decrease in membership. When I started bowling, leagues were the bread and butter of the bowling industry. Bowlers bowled in more than one league and they practiced away from the league. Bowling for fun wasn't anywhere near as popular. Now we have centers where if there isn't a league on the floor the lights are turned off and music is blaring. Not quite the environment for practice. Which in turn can cause some bowlers to not care as much about their game and eventually quit the competitive side of bowling.
The relationship between USBC and BPAA seems to have caused a split in the types of bowlers. And right now, the BPAA side is "winning" if you want to call it that. The two organizations share marketing (if I remember correctly) and thus the goal of that marketing is getting butts in the door. But not necessarily for leagues.
If local associations or proprietors want to increase their league base (for monetary reasons) that is when USBC membership will increase. USBC can showcase the sport of bowling through Team USA, PWBA, High School Bowling, Collegiate Bowling or any other way they can all in hopes of trying to convince the person on their couch to bowl competitively. But once they are in the center, many times it falls on the proprietor to take the next step.