No, it is rubbish!
It's nothing like upgrading a rental car to get a bigger boot and finding no heater installed, because cars have heaters as standard.
Airplane seats differ due to their locations on the aircraft and sometimes differ between one aircraft in the fleet and another.
A leg room seat is a leg room seat and is sold as giving extra legroom. The advertising standards guys wouldn't give a toss about whether it is a recliner or not, they would only be concerned if the leg room seat was in fact not a leg room seat (i.e. standard pitch). As the airline offered a seat with extra leg room, they have fulfilled their part of the contract.
Your suggestion that the airline should advertise leg room seats as being non-reclining is ridiculous. What else should they say? "This leg room seat has no recline facility, it is located at row 11 which means that during the food and drink service you will have to wait approximately 35 minutes to get served. You will have to walk 11 rows to a toilet at the front of the aircraft or 15 rows to the rear" - ludicrous! I was looking through the Boots Christmas gift guide yesterday at all the 'amazing' Christmas gifts they have got this year. The amount of stupid extra information included in the text was ridiculous. There was a picture of an ice cream sundae glass - text said "Ice cream not included", then there was a picture of a banana split bowl - text said "banana not included", but I suppose they have to have text like that to protect themselves from complaints from people like you who would say "But there was a banana in the picture"....