The story
Possibly from a blend of splash + surge, originally US. According to the OED, onomatopoeic.
First known use, by meaning
- from 1911 To spend lavishly or extravagantly, especially money.
- from 1828 An extravagant or ostentatious display.
- from 1928 An extravagant indulgence; a spending spree.
Etymology from Wiktionary, CC BY-SA 4.0.