Homemade handlebar tape? Because road bikes are usually ridden on smooth surfaces, the pedals scraping against the asphalt/gravel/cobblesones/tree roots/sand/mud/dead branches seem to protect the frame and drivetrain against damage. However, the handlebars, instead of projecting metal butts to the inhospitable environment, offer the gentle bar tape of the drops to absorb all the kinetic energy.

At 10EUR/pair, this turns out to be a rather expensive consumable.

One solution I can imagine is homemade bar tape. Some kind of fabric perhaps?

Another would be some protection for the exposed parts of the handlebars, possibly including the very expensive STI levers.

How can crashing with a road bike be made more economical?
If you want to make your bar tape last longer, there are a couple approaches you can take: repair it when it is damaged, or invest in longer-lasting bar tape. Even though it seems like it might be harmless, I would not use improvised bar tape, or no bar tape, or some flat, non-absorbing tape like household electrical tape, as it is actually an important component for both comfort and safety. 

Along with the seat and the pedals, the handlebar is a primary contact point between you and your bike. All of the vibrations your bike feels are transmitted through these contact points. If you try riding a bike without bar tape, your arms will feel those vibrations much more than they would with something to absorb that shock, your arms will get tired much faster. At best it is uncomfortable to ride like this, and at worst it is dangerous, and can make it difficult to use your brakes properly.  

Cheap tape will fray, dry out, or fall apart sooner than nice bar tape. If it does start to fray or fall apart, or if you crash and damage part of it, you can wrap electrical tape around the damaged area to repair it. This will usually hold as long as you need it to. 

Personally I have started using synthetic leather bar tape (Brooks) as it is much more durable than the cheap stuff (2 years old, used almost daily, little sign of wear), and does a really good job at absorbing that vibration. It is heavier and thicker, though, so it's probably not what you'd want to put on a racing bike.