if you're only doing 1 check, I suggest something like a query :
Holiday::where('start', '<=', $now)->where('end', '>=', $now)->exists();
to check if there is a holiday around 'now'.
If you have a list of holidays, and need to check a list of transactions against that holidays list:
// 1 query here
$holidays = Holiday::get();
foreach($transactions as $transaction) {
// no queries here as they are already inside your collection
$isHoliday = $holidays->where('start', '<=', $now)->where('end', '>=', $now)->exists();
dd($transaction, $isHoliday);
}