Do U believe in what I could call 'year-ending riffles' ?  

I don't.
I've got a lot of relatives of mine who spend a lot of 5 euros banknotes (that's the cost of the most common ticket) in such riffles.
I don't.
And I think that I win: for three reasons.
first. I'm a moral winner, since if you play any of such gambling games you want to change your life with a the only use of your being lucky.
second. I always win the ticket fee, since I don't spend a penny for it.
third. Since my relatives buy these tickets, if they have the chance to win... and I have the chance to realize they won... LOL
In our country there is a proverb:
'If you await any help from gambling you'll have your skin full of hair like a bear before you'll get something'.
And this is my opinion.
Take note that on X-mas and other family meeting holidays I've always to invent a new excuse to avoid being catched and forcedly compelled by my relatives to play to '7 and 1/2' a sort of Black Jack and so on where I invariably bet the lowest as possible and try to loose the lowest sum as possible.
At the end of holidays I've a large number of heavy nearly useless coins deriving from such gambling activities.
On the other side I must admit that 3 or 4 times per year I buy a ticket of the tipe 'scratch and win' (we call it scratch and lose). The cost of the ticket is 1 euro, and I just remember once or twice winning occasions: the highest prize I got was 7 euros, which I collected and spent elsewere, since the most stupid thing you can do when you win is continuing to play till you lose everything...
The most delightful thing in this is the fact that sometimes I've my e-mail box flooded of advertisements of casinos proclaming that a winning prize of million dollars is still pending and so on.
If they don't bump on my spam filter, they bump on my indifference...
I just open paid to read advertising emails and so I don't bet anything, since I believe in other things than riffles.