玄史生, CC0, via Wikimedia Commons
I've been looking at various types of ARFF (aircraft rescue and firefighting) apparatus, and while some rapid-response vehicles do appear to be more conventional, most full-size ARFF apparatus tend to have very pointy or curvy front (and sometimes back) ends. I'm curious why ARFF apparatus, especially those at larger airports, tend to be so wildly different from typical Type 1 and Type 2 fire engines.
While the upper portion design enables better visibility, the lower part design is also purposeful:
ARFF needs to be at least somewhat offroadable, as the plane in distress may not have stopped on paved surface. This necessitates the higher ground clearance and steep entry and exit angles. As mentioned in the articles in Quiet Flyers answer, ARFFs are all wheel drive for the aforementioned reason.
The "pointy" and elevated nose of the truck also assists in case the vehicle needs to plow through a foam batch. The foam is diverted under the vehicle instead of rising up along the nose onto the windscreen and hampering visibility.
In addition to the need to travel off road and/or through fences most ARFF vehicles are small batch or even bespoke productions. If you look at special use farm or industrial machinery you will see similar appearance where the design uses structures that can be fabricated from sheet and bar stock, without needing special purpose dies or jigs to make aesthetically pleasing complex curves - think of the shapes you could assemble from paper with scissors and tape.
The vehicle in the photo for example uses three straight beams to make up the wheel arch, and while the crew cab area is curved, most segments only curve in one axis so can be rolled on general purpose equipment without special purpose jigs or dies.
One important difference is that in an Airport Rescue and Fire Fighting (ARFF) truck, an operator may be operating a nozzle (which may be on a boom) from inside the cab, which may at times be positioned very close to the burning aircraft, and so the operator needs good visibility in many directions, including upwards.
Here are a few links of interest that describe some of the special features of ARFF vehicles:
https://www.arffresource.com/2018/12/07/anatomy-of-an-arff-truck/#gref
One minor factor: while ARFF vehicles need to be fast when they are called into action, aerodynamics plays (most probably) no part, or a very small, part in their design.
The main purpose of the depicted fire-fighting vehicle is fighting fires. If they burn an additional gallon when they speed to the emergency scene, that does not matter in terms of their operational cost.
These vehicles aren't your run-of-mill road trucks which manage to run a six or seven digit number of miles/kilometers in their lifetime.
