They'd have to implement a new special case mechanic for this "one-time usage", that cost would likely offset whatever additional revenue is generated by it. If there is additional revenue from such a feature, which I think is questionable at best (as no doubt there will be people buying this instead of the expansion). Note that while buying 100 TP costs us about $1, Turbines revenue from us spending 100 TP is only a fraction of that. Also items with a high TP-price likely have a better TP-to-cash revenue rate than items that cost a smaller TP amount (which can be farmed easily).
Used to play: 85 Champ / Captain / Runekeeper / Guardian, Guild Master of everything but cooking.
Playing now: Hellcat / King Tiger / GW Panther / IS / KV-5 / M4 Sherman and more