Why do advanced car owners sometimes pour diesel urea into a catalyst

Everyone who more or less follows the technologies for reducing the amount of harmful emissions from internal combustion engines, as well as those motorists who have had to drive diesel cars of the EURO-5 class, most likely know perfectly well what AdBlue or “urea” is, and “with than they eat it.” For everyone else, we recall that AdBlue is a trademark under which a special urea solution is sold in Europe – urea H2N-CO-NH2. This substance in the liquid contains 32.5%, and the remaining 67.5% are distilled water.
AdBlue is used in diesel vehicles with selective catalytic converter (SCR). The injection of this solution into the exhaust tract of a modern heavy fuel engine occurs before the catalyst. Under the influence of the high temperature of the exhaust gases, ammonia is released from the urea. Further, it interacts with nitric oxide contained in the gases emitted from the cylinders. The result of a chemical reaction is absolutely harmless to nature and people water vapor and nitrogen.
But we are not interested in this aspect, but in the “folk art” of car owners using AdBlue or its much more affordable analogues sold at Russian gas stations. Note that car owners use urea to improve their technical well-being and gasoline cars too.