Is it frugal to fill the whole gas tank up every pay?

Being on a tight budget can make you question why you do certain things. Sometimes when things aren't as liquid we are forced to make certain decisions regarding how our money is spent.

When living in town and mostly doing short trips, the "budget saving" area looks like fuel. Why fill up the whole gas (petrol) tank if you won't use all of it? Because there are other costs that you don't see right at this minute.

Costs that increase in this method, are due to the fuel systems working harder, with less fuel, and as it barrels down to empty, it drags bits and peices through the fuel filter that it wouldn't necessarily do with more petrol to draw on.

This very fuel glitch, occured, when I was driving my parents car. I had driven to Melbourne and the car just died coming up a hill on a corner. The worst place for the car to die ever. We ended up waiting nearly an hour for road side assistance. I was beside myself upset. The car would only make the sound to say the electrics were ok, however no ignition. The road side assistance arrived and it took him another 10 minutes to decide to check the fuel pump. He kicked and told me to turn the key. I did that and we got some ignition for 2 seconds or so, before it stopped. The guy, informed that the fuel pump was blocked. Instantly I asked, is that my fault. He said that unless, I was filling up with bad fuel, filling up small amounts of petrol at a time, it takes longer than occasional drives. I quickly informed him that I had filled it up completely and that there was more than half a tank left. 

While I didn't need to get any where in particular but back home, and the car dying in a very bad spot with no way to get off the well at all, due to the very steep hill face meeting the edge of the road. The trucks that use the road. It wasn't so bad. However if I had to get to work, for casual shifts or help out a friend in need. I couldn't because I was stuck by the side of the road.

There are a few reasons as to why it pays to fill up the gas (petrol) tank every pay:

To stop the top of the fuel tank rusting. If you regularly fill up small amounts rust starts to build at the top of the tank, as the tank is not vacuum sealed and has a breather hose that lets air in to the tank so it releases the fuel. The breather hose allows air in to the tank, which inturn allows moisture. When there is enough surface rust, and the tank is suddenly filled up, all the rust is washed off the tank and through the fuel system.

The fuel pump, particularly in Commodores VN series, it will stop the car running as without fuel the car doesn't run. Whatever the fuel pump doesn't catch is going through to dirty the injections and other fuel systems in the engine bay.