I'm all for Adverts variant.
First, adverts balance the game.
Adverts strengthen not only Romance decks, but also Horror and Mystery decks too.
Horror can provide a huge amount of coins with strong money enablers: B, 8c C, 8c E, 5c N, Q, V, 5c W, and Y (not counting 'vp or money' cards).
Mystery also has some decent money sources like 5c A, B, 5c I, 4c R, S, and W.
There are just 6 Adventure cards which earn coins without self-trashing: 3c C, D, N, O, X, and 4c Y.
Also some Adventure cards already have a similar feature - immediate prestige from buying cards.
So, it is correct to say 'Adverts disfavor Adventure decks' rather than 'Adverts favor Romance decks'.
Of course Adventure decks can buy adverts too if a player has enough coins to spare.
This happens often when a thinned Adventure deck includes O or at least 2 money cards, or with last minute trashings.
Besides, pure Adventure is the easiest and still a solid deck to run already. A slight rebalancing won't hurt.
Second, adverts reduce luck factor.
Without adverts money from the final turn is practically useless (except for breaking ties).
To turn it into points you have to rely on offer row draws hoping for Adventure cards with immediate prestige.
In other words, sheer luck, unless you've already jailed one in advance.
Third, adverts are not that strong as they seem.
First advert requires 6c and gives 3pts, and second advert awards 6pts in exchange for 9c.
However, in almost all midgame turns, spending those coins for point cards or inks worths more than buying adverts.
For example, buying a card which earns 4pts and costs less than 6c, then incorporating it once or twice is better.
This applies best to Romance decks, since they can cycle cards faster with deck thinning abilities.
After these two adverts, even collecting enough money to buy an advert AND inks to keep the deck rolling both is hard.
So, in short, adverts are usually for endgame pushes or extra point boosts of big coin decks.
I've seen a player buying 20pts advert only once while playing hundreds of games.
Though I don't buy adverts during midgame frequently (my advert points average is <5pts), imo it spices things up and makes the game better.