Gigging in a major city that has little to no mass transit and is spread out like the metro Detroit area is makes it hard to get your crowd to make the trek across town to catch your gig.
For instance, if you are playing a show at the Token Lounge in Westland, you have to try and get people from far away places like Royal Oak or Sterling Heights on the east side and from Taylor and Woodhaven, which are 'downriver'. Most people are not willing to drive that far for a local band, so if you're out of your home turf... good luck drawing anybody. In addition, you have a big open field separating the suburbs from any venues down in the city itself.
Detroit proper is very spread out and it's like a big hole in the middle of the metro area that can either be a help or a hindrance depending on where your fans are from. City dwellers have no problem with shows in the city itself, while suburbanites will show up as long as it's downtown. If it's off the beaten path, many of them are afraid it's going to be a rough neighborhood and won't attend. It's not the venue itself that scares people, it's the neighborhood and what might happen on the way to the car, etc.. A lot of the time this is unfounded fear that grips the people from the 'burbs but it doesn't matter because that fear will keep them away from a lot of shows, especially at night.
Detroit's size is also a hindrance if you want people from Pontiac, Waterford, etc., to go to your show in Lincoln Park or Trenton. The metro Detroit area is among the most spread out big cities in America and not only does it make attendees hard to come by, it makes promotion very difficult and time consuming as well.
One of the end results of this is that a majority of west side bands play west side gigs and east side bands play east side gigs unless a band is trying to spread out to new areas because they have built a big following in their area. Add to that the strict drinking and driving laws and stiff penalties here in Michigan and it becomes that much harder.
By now, you're waiting for me to reveal the solution to you on how to fix this problem and make it all better... guess what? I don't have one. Without mass transit, getting people to drive for longer than your actual set time to come see you on the other side of town is probably not going to happen unless you have some rabid fans.
The only solution I have is to buy a van or rent a limo and pick everybody up and drive them home after the show. That way, nobody has to drive and more importantly, nobody drinks and drives home! Other than that, keep building up your home fan base till you get signed or something.