In Japan, taxis are typically black. Sometimes, they're white or even yellow, but generally, people think of them as being dark-colored and dull looking. These taxis, however, are anything but.
You are looking at "itataku" (痛タク). "Ita" (痛) literally refers to "pain", but it's now slang for things covered with geeky stickers, whether that's cars, snowboards, or bicycles—whatever. The word "pain" refers either to the pain they inflicted on their owners' wallets or the pain unleashed on everyone's eyes. Here, "taku" is short for "takushii" (タクシー) or "taxi".